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181.
Imaging techniques have been introduced to assess the efficacy and toxicity of developing pharmaceuticals. The purpose of this study was to perform a comprehensive characterization of collagen-induced arthritis (CIA) in rats using micro-computed tomography (micro-CT) and to compare the results with data from conventional pathological examination. Arthritis was induced by collagen in 24 female Wistar rats. Micro-CT and pathological analyses were performed to assess arthritis progression. Micro-CT analysis showed marked joint destruction occurring in a time-dependent manner following collagen administration. Bone volume was significantly decreased in the tibia at weeks 3 and 4 compared to week 0 (p < 0.05 and p < 0.01, respectively). Additionally, percent bone volume was significantly reduced in the tibia at week 4 compared to week 0 (p < 0.05). In contrast, bone surface/bone volume and trabecular separation were significantly increased in the tibia of the animals at week 4 compared to week 0 (p < 0.05). Severe joint destruction with extensive inflammation, erosion of cartilage and bone, and infiltration of inflammatory cells were observed in the knee joints of the collagen-treated rats. Taken together, micro-CT made it possible to quantify CIA lesions and should be performed with pathological examination in rats.  相似文献   
182.
Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H2O2)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H2O2 in a dose-dependent manner. Additionally, H2O2 treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H2O2 significantly attenuated the H2O2-induced decrease of cell viability. H2O2 exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H2O2-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H2O2-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H2O2-induced apoptosis by inhibiting ROS generation.  相似文献   
183.
This study was conducted to determine whether serum adipokine concentrations differed between healthy dogs and dogs with diabetes mellitus (DM). To accomplish this, 19 dogs with newly diagnosed DM were compared to 20 otherwise healthy dogs. The serum concentrations of visfatin, leptin, IL-1β, IL-6, IL-18, and TNF-α were significantly higher in diabetic dogs than in healthy dogs, whereas the serum adiponectin concentrations were lower in diabetic dogs. However, there were no significant differences in the IL-10 and resistin levels between groups. The serum leptin concentrations in diabetic dogs with and without concurrent disorders differed significantly. Treatment with insulin induced a significant decrease in IL-6 in diabetic dogs without concurrent disorders. These results show that the clinical diabetic state of dogs could modulate the circulating visfatin and adiponectin concentrations directly, while upregulation of leptin was probably a result of concurrent disorders rather than an effect of persistent hyperglycemia as a result of DM.  相似文献   
184.
The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n‐6/n‐3. Carcasses of roughage‐fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain‐fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world.  相似文献   
185.
ObjectiveTo evaluate the fresh gas flow (FGF) rate requirements for the Humphrey ADE semi-closed breathing system in the Mapleson A mode; to determine the FGF at which rebreathing occurs, and compare the efficiency of this system to the Bain (Mapleson D) system in spontaneously breathing cats and small dogs.Study DesignProspective clinical study.AnimalsTwenty-five healthy (ASA score I or II) client-owned cats and dogs (mean ± SD age 4.7 ± 5.0 years, and body weight 5.64 ± 3.26 kg) undergoing elective surgery or minor procedures.MethodsAnaesthesia was maintained with isoflurane delivered via the Humphrey ADE system in the A mode using an oxygen FGF of 100 mL kg−1 minute−1. The FGF was then reduced incrementally by 5–10 mL kg−1minute−1 at approximately five-minute intervals, until rebreathing (inspired CO2 >5 mmHg (0.7 kPa)) was observed, after which flow rates were increased. In six animals, once the minimum FGF at which rebreathing occurred was found, the breathing system was changed to the Bain, and the effects of this FGF delivery examined, before FGF was increased.ResultsRebreathing did not occur at the FGF recommended by the manufacturer for the ADE. The mean ± SD FGF that resulted in rebreathing was 60 ± 20 mL kg−1minute−1. The mean minimum FGF at which rebreathing did not occur with the ADE was 87 ± 39 mL kg−1minute−1. This FGF resulted in significant rebreathing (inspired CO2 8.8 ± 2.6 mmHg (1.2 ± 0.3 kPa)) on the Bain system.ConclusionsThe FGF rates recommended for the Humphrey ADE are adequate to prevent rebreathing in spontaneously breathing cats and dogs <15 kg.Clinical relevanceThe Humphrey ADE system used in the A mode is a more efficient alternative to the Bain system, for maintenance of gaseous anaesthesia in spontaneously breathing cats and small dogs.  相似文献   
186.
Rodents are recognized reservoir hosts for many human zoonotic pathogens. The current trends resulting from anthropocene defaunation suggest that in the future they, along with other small mammals, are likely to become the dominant mammals in almost all human‐modified environments. Recent intricate studies on bat‐borne emerging diseases have highlighted that many gaps exist in our understanding of the zoonotic transmission of rodent‐borne pathogens. This has emphasized the need for scientists interested in rodent‐borne diseases to integrate rodent ecology into their analysis of rodent‐borne pathogen transmission in order to identify in more detail the mechanisms of spillover and chains of transmission. Further studies are required to better understand the true impact of rodent abundance and the importance of pathogen sharing and circulation in multi‐host– multi‐pathogen communities. We also need to explore in more depth the roles of generalist and abundant species as the potential links between pathogen‐sharing, co‐infections and disease transmission.  相似文献   
187.
188.
Fourier transform mid-infrared (FT-IR) spectroscopy was investigated as a method of analysis for trans fatty acid content of cereal products without the need for prior oil extraction. Spectra were obtained, with an FT-IR spectrometer equipped with an attenuated total reflectance (ATR) device, of ground samples pressed onto the diamond ATR surface, and trans fatty acids were measured by a modification of AOAC Method 996.01. Partial least-squares (PLS) models were developed for the prediction of trans fatty acids in ground samples using several wavenumber selections on the basis of bands related to lipids. The models (n = 79) predicted trans fatty acids in ground samples with standard error of cross-validation (SECV) of 1.10-1.25 (range 0-12.4) % and R2 of 0.85-0.88 and in validation samples (n = 26) with standard error of performance (SEP) of 0.96-1.12 (range 0-12.2) % and r2 of 0.89-0.92, indicating sufficient accuracy for screening. Sample trans fatty acid % was predicted as accurately with the fingerprint region (1500-900 cm(-1)) as with the entire range (4000-650 cm(-1)) indicating, in concert with the regression coefficients, the importance of the isolated trans double bonds at 966 cm(-1) in development of the model. Data is also presented on prediction of trans fatty acids using the spectra of residual oil films on the ATR surface after removing the solid portion of the sample.  相似文献   
189.
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents.  相似文献   
190.
The acaricidal activity of materials derived from rhizome of Atractylodes ovata (Atractylodes macrocephala) toward adult Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using fabric-circle residual contact and vapor-phase toxicity bioassays. Results were compared with those of the currently used acaricides: benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (Deet). The active principles of A. ovata rhizome were identified as the sesquiterpenoids, atractylenolide III (1) and atractylon (2), by spectroscopic analysis. In fabric-circle residual contact bioassays with adult D. farinae, atractylenolide III (LD50, 103.3 mg/m2) and atractylon (136.2 mg/m2) were five and four times more toxic than Deet and 1.7- and 1.3-fold more active than dibutyl phthalate, respectively, based on 24 h LD50 values. These compounds were less toxic than benzyl benzoate (LD50, 45.8 mg/m2). Against adult D. pteronyssinus, atractylenolide III (LD50, 73.8 mg/m2) and atractylon (72.1 mg/m2) were eight times more active than Deet and 2.5-fold more toxic than dibutyl phthalate. These compounds were slightly less effective than benzyl benzoate (LD50, 46.0 mg/m2). In vapor-phase toxicity tests with both mite species, atractylenolide III and atractylon were effective in closed but not in open containers. These results indicate that the effect of these sesquiterpenoids was largely a result of action in the vapor phase. Naturally occurring atractylenolide III and atractylon merit further study as potential house dust mite control agents or leads because of their great activity as a fumigant.  相似文献   
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